title: Evidence of local anisotropic strains in relaxor ferroelectrics below intermediate temperature T* detected by acoustic emission.
abstract: Oriented {100}-, {110}-, and {111}-cuts of Pb₀.₇₈)Ba₀.₂₂Sc₀.₅Ta₀.₅O₃ single crystals have been studied by means of the acoustic emission (AE) method during their thermal cycling in the temperature range of 300-600 K. For all crystal orientations pronounced AE signals have been detected near 490 K, which corresponds to the intermediate temperature T(*). However, the highest AE count rate has been detected from {110}-oriented cuts, revealing strong anisotropic coupling between the existing polar species that at T(*) merge into larger regions of polarization (PNRs). The temperature's hysteresis is revealed to be 15 K, indicating that the transformation processes at T(*) can be considered as local Martensitic-like ferroelectric transitions inside PNRs. The interplay between PNRs and ultrahigh local strains of perovskite-type relaxor ferroelectrics is discussed.
authors.affiliation: Faculty of Science, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
authors.forename: E
authors.initials: E
authors.lastname: Dul'kin
authors.forename: B
authors.initials: B
authors.lastname: Mihailova
authors.forename: M
authors.initials: M
authors.lastname: Gospodinov
authors.forename: E
authors.initials: E
authors.lastname: Mojaev
authors.forename: M
authors.initials: M
authors.lastname: Roth